14717: Rename WebsocketKeepaliveTimeout to SendTimeout and add a comment

[arvados.git] / services / crunchstat / crunchstat.go

diff --git a/services/crunchstat/crunchstat.go b/services/crunchstat/crunchstat.go
index 510df3bac676afbc56589e5343b0a20e002baea7..7e2dc01271f0f08e09129772badc8402cc1b786e 100644 (file)
--- a/services/crunchstat/crunchstat.go
+++ b/services/crunchstat/crunchstat.go
@@ -1,8 +1,13 @@
+// Copyright (C) The Arvados Authors. All rights reserved.
+//
+// SPDX-License-Identifier: AGPL-3.0
+
 package main
 
 import (
        "bufio"
        "flag"
+       "fmt"
        "io"
        "log"
        "os"
@@ -16,8 +21,11 @@ import (
 
 const MaxLogLine = 1 << 14 // Child stderr lines >16KiB will be split
 
-var signalOnDeadPPID int
-var ppidCheckInterval = time.Second
+var (
+       signalOnDeadPPID  int = 15
+       ppidCheckInterval     = time.Second
+       version               = "dev"
+)
 
 func main() {
        reporter := crunchstat.Reporter{
@@ -27,14 +35,25 @@ func main() {
        flag.StringVar(&reporter.CgroupRoot, "cgroup-root", "", "Root of cgroup tree")
        flag.StringVar(&reporter.CgroupParent, "cgroup-parent", "", "Name of container parent under cgroup")
        flag.StringVar(&reporter.CIDFile, "cgroup-cid", "", "Path to container id file")
-       flag.IntVar(&signalOnDeadPPID, "signal-on-dead-ppid", 15, "Signal to send child if crunchstat's parent process disappears")
+       flag.IntVar(&signalOnDeadPPID, "signal-on-dead-ppid", signalOnDeadPPID, "Signal to send child if crunchstat's parent process disappears (0 to disable)")
        flag.DurationVar(&ppidCheckInterval, "ppid-check-interval", ppidCheckInterval, "Time between checks for parent process disappearance")
        pollMsec := flag.Int64("poll", 1000, "Reporting interval, in milliseconds")
+       getVersion := flag.Bool("version", false, "Print version information and exit.")
 
        flag.Parse()
 
+       // Print version information if requested
+       if *getVersion {
+               fmt.Printf("crunchstat %s\n", version)
+               return
+       }
+
+       reporter.Logger.Printf("crunchstat %s started", version)
+
        if reporter.CgroupRoot == "" {
                reporter.Logger.Fatal("error: must provide -cgroup-root")
+       } else if signalOnDeadPPID < 0 {
+               reporter.Logger.Fatalf("-signal-on-dead-ppid=%d is invalid (use a positive signal number, or 0 to disable)", signalOnDeadPPID)
        }
        reporter.PollPeriod = time.Duration(*pollMsec) * time.Millisecond
 
@@ -84,11 +103,11 @@ func runCommand(argv []string, logger *log.Logger) error {
 
        // Kill our child proc if our parent process disappears
        if signalOnDeadPPID != 0 {
-               go sendSignalOnDeadPPID(signalOnDeadPPID, os.Getppid(), cmd, logger)
+               go sendSignalOnDeadPPID(ppidCheckInterval, signalOnDeadPPID, os.Getppid(), cmd, logger)
        }
 
        // Funnel stderr through our channel
-       stderr_pipe, err := cmd.StderrPipe()
+       stderrPipe, err := cmd.StderrPipe()
        if err != nil {
                logger.Fatalln("error in StderrPipe:", err)
        }
@@ -102,13 +121,14 @@ func runCommand(argv []string, logger *log.Logger) error {
        os.Stdin.Close()
        os.Stdout.Close()
 
-       copyPipeToChildLog(stderr_pipe, log.New(os.Stderr, "", 0))
+       copyPipeToChildLog(stderrPipe, log.New(os.Stderr, "", 0))
 
        return cmd.Wait()
 }
 
-func sendSignalOnDeadPPID(signum, ppidOrig int, cmd *exec.Cmd, logger *log.Logger) {
-       for _ = range time.NewTicker(ppidCheckInterval).C {
+func sendSignalOnDeadPPID(intvl time.Duration, signum, ppidOrig int, cmd *exec.Cmd, logger *log.Logger) {
+       ticker := time.NewTicker(intvl)
+       for range ticker.C {
                ppid := os.Getppid()
                if ppid == ppidOrig {
                        continue
@@ -120,9 +140,10 @@ func sendSignalOnDeadPPID(signum, ppidOrig int, cmd *exec.Cmd, logger *log.Logge
                logger.Printf("notice: crunchstat ppid changed from %d to %d -- killing child pid %d with signal %d", ppidOrig, ppid, cmd.Process.Pid, signum)
                err := cmd.Process.Signal(syscall.Signal(signum))
                if err != nil {
-                       logger.Printf("error: sending signal: %d", err)
+                       logger.Printf("error: sending signal: %s", err)
                        continue
                }
+               ticker.Stop()
                break
        }
 }